If nothing else works, Charles Stuart Platkin, the "Diet Detective," will badger you into losing weight.
There was Jennifer Cadle, 276 pounds. He bought her a huge chocolate cake - her weakness - and had her cut a slice and put it in a box. "You'd have to walk 2-1/2 hours to work that off," he told her.
Then he made her walk the 2-1/2 hours carrying the boxed slice of cake.
"At least let me eat the cake," she pleaded.
"You're not eating that cake," he barked.
At 399-pound Micah Molinari's house, Platkin purged the refrigerator of fattening foods and poured a gallon of rum down the drain.
"That hurt," Molinari recalls. "I do enjoy my cocktails."
Both interventions were public, featured on Platkin's WE-TV cable network program "I Want to Save Your Life," a reality show for the overweight.
He makes no apology. "These people have really reached the last straw. They're looking for help."
His diet plans seem pretty standard -- avoid red meat; eat chicken, fish, vegetables, egg whites, oatmeal, skim milk and such. His exercise plans seem unremarkable, too -- walking, core training, yoga.
Motivation is the key for Platkin, an associate professor of public health at Florida International University and the author of five books, including "The Diet Detective's Count Down." He also writes a newspaper nutrition column and dispenses advice at www.dietdetective.com.
Platkin pries into his clients' lives to see what's important to them, then persuades them they're going to lose that if they don't take off pounds.
It worked on Molinari: "I have a 5-year-old daughter, Sydney. She's my life. I need to be healthy so I'm there when she needs me." He lost 100 pounds in 17 weeks.
In preparing for the TV show, Platkin requires diet clients to fill out a 40-page questionnaire. They also must give him permission to interrogate family and friends and show up without warning.
One Saturday six months ago, Molinari was hanging with friends when one of them said, "I'm starving. Let's order a pizza."
As secretly prearranged, she called Platkin, not Pizza Hut.
Molinari recalls: "About half an hour later there's a knock on my door. There's this pizza guy with a box. But he calls me by name and cameras come flying out of everywhere. I almost had a heart attack."
It was Platkin with a TV crew. They brought the ingredients not for Molinari's usual meat lovers' pizza, but for one with whole grain crust, low-fat mozzarella, fresh basil, tomatoes and garlic.
They made it on the spot.
"I was surprised," says Molinari, 31. "It actually tasted pretty good."
Although Platkin might spend several days with the clients he features on his TV show, he also peppers his regular online clients with information.
They can sign up for a $4-a-week subscription weight-loss program with custom menus, recipes and shopping lists.
Platkin says dieters should rely not on willpower but on research and planning. If you're going to dine at a new restaurant, visit its Web site first and scan the menu for the healthiest choices. By deciding what to eat in advance, you avoid impulsive decisions made while hungry.
Growing up in New York, Platkin was always heavy. "I liked cake and pizza. I was always 30 to 50 pounds overweight."
Diets never worked: "I was ostracized in school. I was called fat by a teacher once. It was traumatic."
As he reached his 30s, he worried about his health. Platkin's epiphany came after he receiveda law degree from Cornell University, realized he didn't want to be a lawyer and was working up a pitch for a magazine story on how people could learn to change lifelong behaviors. He had pored over behavioral studies, consulted experts and drafted an outline.
"But I didn't believe a word I'd written," he says. "I knew it in theory, but in practice I thought it was hogwash. Finally I decided I had to apply it to myself. It changed my life."
Platkin wrote his first book, "Breaking the Pattern," in 2002 and applied it to himself. Today, at 46 and 5 feet 9 inches tall, he weighs 164 pounds.
In 2001, wanting to leave Manhattan after 9/11, Platkin and wife Shannon moved to Miami. He received a master's in public health from FIU and is working on his doctorate.
Sometimes, they cry
Platkin's motivational techniques can be hard on dieters.
In one episode, he reduced 258-pound Sussy Taveras to tears by telling her she was in danger of dying from a heart attack and never seeing her daughter graduate from college.
Under Platkin's guidance, she went from 258 to 203 pounds in six months, with a goal of 140 pounds.
"He told me what I needed to hear. He said, 'You're a strong, powerful woman.' He made me feel like I was worth the time."